US 6,362,454 B1 · Method for drilling circular holes with a laser beam

Abstract

A method and apparatus for machining a work piece with a laser beam to form a circular hole in the work piece applies the laser beam to a beam rotator which rotates the laser beam about an axis of rotation before it is applied to the work piece. In one embodiment, a laser generates a laser beam having a beam area and a beam axis within the beam area. A beam rotator rotates the laser beam about the beam axis and directs the rotating laser beam to the work piece. One beam rotator employs three reflective surfaces which invert the beam across only one axis defined in the beam cross-section. Another beam rotator employs a triangular prism which receives the laser beam at a first surface at an angle of incidence equal to the Brewster's angle for the prism, totally internally reflects the laser beam from a second surface to direct the light out of the prism through a third surface. This beam rotator also employs a rotating half wave plate to ensure that the light entering the prism is p-polarized. The rotating laser beam produced by the beam rotator may be focussed into a single focussed rotating beam or diffracted to form multiple rotating laser beams.

Claims27

Dependent claims

A method for drilling holes in a work piece with a laser comprising the steps of:

receiving a laser beam having a beam cross section with a predetermined angular orientation and directed along a beam axis located with the beam cross section;
rotating the laser beam about an axis of rotation, substantially parallel to the beam axis, and directing the rotating laser beam toward the work piece, wherein the angular orientation of the beam cross section changes as the beam is rotated.

Dependencies are inferred from the claim text.

Method for drilling circular holes with a laser beam

Life of this patent

Method for drilling circular holes with a laser beam

Life of this patent

Abstract

Claims27